Material relations between things
To say that money expresses a material relation between things is to emphasize that money exists as a connection between the differing aspects of commodity production in the physical labour process itself.
Distinguishing characteristics of money as a material relation between things include:
- In the capitalist mode of production, "[i]t is... precisely this finished form of the world of commodities—the money form—which conceals the social character of private labour and the social relations between the individual workers, by making those relations appear as relations between material objects, instead of revealing them plainly."
"Hence, when we bring the products of our labour into relation with each other as values, it is not because we see in these articles the material receptacles of homogeneous human labour. Quite the contrary: whenever, by an exchange, we equate as values our different products, by that very act, we also equate, as human labour, the different kinds of labour expended upon them. We are not aware of this, nevertheless we do it. Value, therefore, does not stalk about with a label describing what it is. It is value, rather, that converts every product into a social hieroglyphic. Later on, we try to decipher the hieroglyphic, to get behind the secret of our own social products; for to stamp an object of utility as a value, is just as much a social product as language." [Karl Marx, Capital, Volume 1, Chapter 1, Section 4]
"When, therefore, Galiani says: Value is a relation between persons – “La Ricchezza e una ragione tra due persone,” – he ought to have added: a relation between persons expressed as a relation between things. (Galiani: Della Moneta, p. 221, V. III. of Custodi’s collection of “Scrittori Classici Italiani di Economia Politica.” Parte Moderna, Milano 1803.)" [Marx, Capital, Volume I, Chapter 1, Section 4, footnote 28]